The present invention relates to a process for de-twisting and craping a cloth woven with highly twisted yarns, the object being to de-twist the twisted yarns of the cloth so as to form fine crapes all over the cloth.
Twisted yarns for constructing a cloth usually have 600 to 2500 twists per meter and the cloth obtained can be craped by de-twisting the yarns constructing the cloth.
The craping of cloth of this kind has conventionally been done as follows: A cloth with a limited length is wound around a frame, and the hems of the wound cloth are sewn together; a plurality of the unit bodies thus obtained are introduced in a drum rotating in a batch to give an impact to the unit bodies by the rotation of the drum while elevating the temperature of the wet heat in the batch successively in a heating pattern, for instance, as shown in FIG. 1; and cooling the interior of the batch slowly down to about 40.degree. C. when the temperature of the batch reaches about 100.degree. C., and then the cloth is taken out from the drum.
However, such a conventional cloth craping process has various defects such as:
a. A process is needed to wind the cloth of a definite length around a frame, deteriorating the workability.
b. Since the cloth is sewn together after winding it around the frame, the craping of the cloth is done insufficiently.
c. Since the treatment is done discontinuously, the productivity is low.
d. The batch must be opened every time in replacing the cloth in the drum to set free the wet heat in the batch completely, deteriorating the heat efficiency.
e. The wet heat condition in the batch can hardly be maintained constant in each of the operations, so that uniform craping of a series of cloths can by no means be expected.
Accordingly, the present invention is to offer a new continuous process for the craping of a cloth to eliminate various defects in craping as above mentioned.